1. Technical Field
The present invention relates to fiber optics systems and, more particularly, to wavelength division multiplexing with polymer waveguides.
2. Description of the Related Art
Optical data transfer is increasingly used in high-performance computing, where short-range optical communication provides a fast and low power alternative to electrical communication. However, despite these developments, new multi-core processing architectures demand higher bandwidth and density. The number of channels needed to transfer information is increasing rapidly. In the most advanced systems, more than 60,000 individual fibers are used, so that practical physical limits are being rapidly reached.
Efforts have been made to use a single fiber to carry multiple data signals at different wavelengths. This increases the total bandwidth of a system without a corresponding increase in the number of physical channels, but existing wavelength division multiplexing solutions are difficult to implement on optical printed circuit board technology. In one notable example, a dielectric mirror is formed in a waveguide at a forty-five degree angle to the direction of transmission. The mirror is made to be selectively reflective, such that one wavelength is reflected out of the waveguide path while the other wavelengths are passed through.
However, it is difficult to form such a reflector on a polymer waveguide, it is difficult to form structures on a forty-five degree angle due to shadow effects, and the reflector itself must be relatively thick due to a large polarization dependency that results from the forty-five degree angle of incidence.